fun loudspeaker with one sided diy alu foil tweak
original cone
more info on tweaking a portable battery powered bluetooth box
original cone
more info on tweaking a portable battery powered bluetooth box
fun loudspeaker portable bluetooth
some info on how I modified it
added damping
added 1 ohm in line with the bass for a little bit of current drive by added resistance
EQ for corner placement (you can really gain headroom like this!)
EQ for against back wall
some info on how I modified it
added damping
added 1 ohm in line with the bass for a little bit of current drive by added resistance
EQ for corner placement (you can really gain headroom like this!)
EQ for against back wall
This is how a "book" of thin metal looks like
you can easily cut many foils in one time sparing lots of work
this metal foil you get from the goldsmith
you can easily cut many foils in one time sparing lots of work
this metal foil you get from the goldsmith
I'm so lucky I could get a bit of space between paper cone and plastic enclosure.
Other piezo tweets have no space available and must be desoldered and resoldered to do this
Other piezo tweets have no space available and must be desoldered and resoldered to do this
someone would say that the aluminium foil could be applied more perfect following the round shape of the paper cone.
Since I read about the patent from Scan Speak about the NRSC cone where the round edge is treated by disturbing its regularity I am less concerned about a "perfect" application of the foil.
Which can be done.
But must not be better acoustically than the more irregular appearing application of metal foil.
Since I read about the patent from Scan Speak about the NRSC cone where the round edge is treated by disturbing its regularity I am less concerned about a "perfect" application of the foil.
Which can be done.
But must not be better acoustically than the more irregular appearing application of metal foil.
where do you get a really fine damping material from for free?
Not using "elves hair" expensive damping or searching a long time for something similar
drying machines for clothes offer it
Not using "elves hair" expensive damping or searching a long time for something similar
drying machines for clothes offer it
15inch fullrange from Monacor I had 20 years lying around. Which I aluminized with thin foil then.
Today I would use thicker household alu foil for a big driver like this:
Monacor SP385G
it has a nice copper faraday ring on the pole piece
made a diy alu whizzer but its too small. Need to make another one.
i removed the zobel network
at that time I was also damping the yellow spider with baf wadding. Today I leave this area as is.
Today I would use thicker household alu foil for a big driver like this:
Monacor SP385G
it has a nice copper faraday ring on the pole piece
made a diy alu whizzer but its too small. Need to make another one.
i removed the zobel network
at that time I was also damping the yellow spider with baf wadding. Today I leave this area as is.
Hey you ever did a screw on piezo compression driver if you did how was the sound and measurement before and after curious on improving my piezo compression drivers
Maybe I measured that years ago when I was more serious with that.
But damping metal baskets of fullrange drivers (behind the paper cone) and damping cavities of tweeters rarely show big differences in frequency response what could explain the dominant difference in sound you can hear.
Maybe waterfall measurement can show something.
But for sure this damping is dramatically audible.
The reason for this are broadband reflections only a bit less loud than the emanation from the cone.
So just try and make a listening test a / b comparison.
This could be recorded and with a headphone you could judge on this and others, too.
I do all this so many years and listened to it often.
I do not need to make a scientific proof. Who wants to reproduce an experiment has input on how to do and can post measurements himself.
From a formal standpoint its better if I am not the only one trying something out and documenting it.
I posted here several times waterfall measurements for the alu foil tweak giving strong hints that the foil tweak is effective against resonances.
But damping metal baskets of fullrange drivers (behind the paper cone) and damping cavities of tweeters rarely show big differences in frequency response what could explain the dominant difference in sound you can hear.
Maybe waterfall measurement can show something.
But for sure this damping is dramatically audible.
The reason for this are broadband reflections only a bit less loud than the emanation from the cone.
So just try and make a listening test a / b comparison.
This could be recorded and with a headphone you could judge on this and others, too.
I do all this so many years and listened to it often.
I do not need to make a scientific proof. Who wants to reproduce an experiment has input on how to do and can post measurements himself.
From a formal standpoint its better if I am not the only one trying something out and documenting it.
I posted here several times waterfall measurements for the alu foil tweak giving strong hints that the foil tweak is effective against resonances.
Why not simply spray paint the color you want, they sell metallic can, job done in 15 min, multiple coats as needed
finished portable Soundbox with one side tweeter which can be put on and off.
Aluminized paper cone, both sides. Diy dustcap after removing the paper one.
Aluminized piezo tweeter with crossover 100 ohm parallel, 0.3uF Mkp condenser
Reflex low tuned to 30hz.
Egg crates inside, the real ones.
Here some more fotos
Aluminized paper cone, both sides. Diy dustcap after removing the paper one.
Aluminized piezo tweeter with crossover 100 ohm parallel, 0.3uF Mkp condenser
Reflex low tuned to 30hz.
Egg crates inside, the real ones.
Here some more fotos
Attachments
@L.rivera92172
I measured in another thread the aluminium tweak on piezo tweeter paper cones (thin foil).
With nearly no taming of the piezo type resonances. Only a little bit effect on the waterfall.
Here someone measured a thin cavity damping in a piezo (use translation) but with no effect on the f response or waterfall:
https://hifi-selbstbau.dyndns.org/html/piezo_horn.html
But, I know from listening tests that alu foil on paper cones - also piezo drivers make a big difference.
This I checked only with f response and waterfall. I never did much distortion tests maybe here can be seen much more.
I measured in another thread the aluminium tweak on piezo tweeter paper cones (thin foil).
With nearly no taming of the piezo type resonances. Only a little bit effect on the waterfall.
Here someone measured a thin cavity damping in a piezo (use translation) but with no effect on the f response or waterfall:
https://hifi-selbstbau.dyndns.org/html/piezo_horn.html
But, I know from listening tests that alu foil on paper cones - also piezo drivers make a big difference.
This I checked only with f response and waterfall. I never did much distortion tests maybe here can be seen much more.
@L.rivera92172
motorola damped the piezo disc itself with a thin rubber sheet. Today nobody does that anymore.
Could be that this tweak - maybe some silicone glue instead - is really doing something mechanically against piezo ringing.
However I use the piezos only with a simple 6db crossover and aluminium foil tweak and find them like this already soundig great due to their transient capabilities.
Here they excel over most classic dynamic tweeters. Thats my personal experience.
If they would sound cheap and distorted I won't use them.
Above 5khz the ear is much less susceptible for distortion or resonances. So they work.
motorola damped the piezo disc itself with a thin rubber sheet. Today nobody does that anymore.
Could be that this tweak - maybe some silicone glue instead - is really doing something mechanically against piezo ringing.
However I use the piezos only with a simple 6db crossover and aluminium foil tweak and find them like this already soundig great due to their transient capabilities.
Here they excel over most classic dynamic tweeters. Thats my personal experience.
If they would sound cheap and distorted I won't use them.
Above 5khz the ear is much less susceptible for distortion or resonances. So they work.
Thank you for this i got a piezo compression driver that plays from 800hz and up im going to try this on it and some 8in papercone midbass to see how they sound
finished loudspeaker and some easy EQ makes it tonally correct.
As it is a fullrange going up to 4khz the piezo tunes in perfectly.
Its pretty high end with applied EQ.
Unequalized EQ response in red
As it is a fullrange going up to 4khz the piezo tunes in perfectly.
Its pretty high end with applied EQ.
Unequalized EQ response in red
Attachments
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